In prior systems, an umbrella which can be automatically opened and closed includes at least two coil springs in its shaft. One spring is compressed and the other is in tension. When a user is going to open or to close the umbrella, he must use enough force to overcome the total force of two springs, changing the state of both springs. Such an umbrella can be easily operated by a normal man, however, if the user is a woman or a child, they would obviously find it hard to operate this type of umbrella.